15309972 has 72 divisors (see below), whose sum is σ = 42296800. Its totient is φ = 4828896.

The previous prime is 15309967. The next prime is 15309997. The reversal of 15309972 is 27990351.

15309972 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 18054 + ... + 18882.

Almost surely, 2^15309972 is an apocalyptic number.

15309972 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 15309972, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21148400).

15309972 is an abundant number, since it is smaller than the sum of its proper divisors (26986828).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

15309972 is a wasteful number, since it uses less digits than its factorization.

15309972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 867 (or 853 counting only the distinct ones).

The product of its (nonzero) digits is 17010, while the sum is 36.

The square root of 15309972 is about 3912.7959313003. The cubic root of 15309972 is about 248.3084308568.

The spelling of 15309972 in words is "fifteen million, three hundred nine thousand, nine hundred seventy-two".